package com.api.phm.util;

import java.math.BigInteger;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

public class MD5Utils {
    /**
     * 使用md5的算法进行加密
     */
    public static String md5(String plainText) {
        byte[] secretBytes = null;
        try {
            secretBytes = MessageDigest.getInstance("md5").digest(
                    plainText.getBytes());
        } catch (NoSuchAlgorithmException e) {
            throw new RuntimeException("没有md5这个算法！");
        }
        String md5code = new BigInteger(1, secretBytes).toString(16);// 16进制数字
        // 如果生成数字未满32位，需要前面补0
        for (int i = 0; i < 32 - md5code.length(); i++) {
            md5code = "0" + md5code;
        }
        return md5code;
    }

    /**
     * 可逆的的加密解密方法；两次是解密，一次是加密
     *
     * @param inStr
     * @return
     */
    public static String convertMD5(String inStr) {

        char[] a = inStr.toCharArray();
        for (int i = 0; i < a.length; i++) {
            a[i] = (char) (a[i] ^ 't');
        }
        String s = new String(a);
        return s;

    }


    public static void main(String[] args) {
        String s = md5("1234");
        System.out.println("MD5后：" + s);
        System.out.println("MD5后再加密：" + convertMD5(s));
        System.out.println("MD5加密后解密：" + convertMD5(convertMD5(s)));
        String s2 = convertMD5("12345");
        System.out.println("可逆的加密解密方法之加密：" + s2);
        System.out.println("可逆的加密解密方法之解密：" + convertMD5(s2));


//        // AES 对称加密示例
//        String plaintext = "Hello, world!";
//        String password = "secretPassword";
//        // AES 加密
//        String encryptedAES = EncryptionUtil.encryptWithAES(plaintext, password);
//        System.out.println("AES Encrypted: " + encryptedAES);
//        // AES 解密
//        String decryptedAES = EncryptionUtil.decryptWithAES(encryptedAES, password);
//        System.out.println("AES Decrypted: " + decryptedAES);
    }

}
